Tuesday, June 18, 2013

UnexpetectedExchagneAuthBlob

While testing mail flow before an Exchange 2007 to Exchange 2013 migration is received the following error from an Exchange 2013 server to an Exchange 2007 server:
454 4.7.0 Temporary authentication failure
Further investigation in the SMTP receive protocol log showed this error:
Inbound ExchangeAuth negotiation failed because of UnexpetectedExchagneAuthBlob
Luckily based on some quick searches I was able to identify time synchronization as the source of the issue. Active Directory authentication starts to fail when time synchronization is not within 5 minutes. In this case the time difference was 6 minutes.

In the short term, I change the time on one server and verified that mail flow started to work properly. Long run I need to identify why time what not properly synchronized and fix it.

1 comment:

  1. If you have DCs running on VMs, you may have to disable time synchronization on Hyper-V host, then correct DCs to sync with PDC server. Even though the time looks correct.

    ReplyDelete